Watch-balance.



D. B. RAFF.

WATCH BALANCE.

TION FILED NOV 29 APPLICA l9l3- '1 ,1 91 ,462. v Patented July 18, 1916.

UNITED STATES PATENT ()FFICE.

DERWOOD B. RAFF, OF THOIvI'AS, OKLAHOMA.

\VATCH-BALANCE.

Application filed November 29, 1913.

To all whom it may concern Be it known that I, DERwooD B. RAFF, a citizen of the United States, residing at Thomas, in the county of Custer and State of Oklahoma, have invented certain new and useful Improvements in lVatch-Balances, of which the following is a specification.

'It is one of the objects of my invention to prevent a watch balance from getting out of poise and to provide improved means for lengthening or shortening the hair spring to maintain poise without the necessity of adding timing washers or undercutting balance screws.

My invention includes the provision of fixed and adjustable collets tofwhich the hair spring is secured and by means of which adjustment of the hair spring can be obtained by the movable collet, only after'the hair ppring has been released from the fixed col- The device of my invention will be more fully described in connection with the accompanying drawing and will be more particularly pointed out and ascertained in and by the appended claims.

In the drawing :Figure 1 is a view in side elevation looking at the balance cap and illustrating the regulator and hair spring with the balance wheel actuated by the latter. Fig. 2 is a View looking in a direction reverse from the direction from which Fig. 1 is viewed. Fig. 3 is a sectional view on line 33 of Fig. 1. Fig. 4 is a sec tional view on line H of Fig. 2.

Like characters of reference designate similar parts throughout the different figures of the drawing.

As illustrated, 1 designates the balance cap of a watch movement in which is journaled one end 2 of a balance arbor. A balance wheel is indicated at 3 and a hair spring at 4. A regulator is shown at 5 and one end of the hair spring 4: is shown fixed to the balance arbor 2, as indicated at 6.

The free end 7 of the hair spring 1 is extended through means which may be in the form of a collet 8, fixed by a screw 16 to the balance cap 1, to permit removal dur ing repair work. The collet S is provided with an opening through which the end 7 of the hair spring projects and a screw 9 serves to anchor the hair spring in the collet 8.

Specification of Letters Patent.

Patented July 18, 1916.

Serial No. 203,795.

The balance cap 2 is provided with a slot 10, preferably of arcuate form, in which an adjustable collet is slidably mounted. As shown more particularly in Fig. 3, the ad justable collet is provided with a slot-engaging portion 11, of polygonal cross-section so that it will slidably but non-rotatably engage the walls of the slot 10. Said portion 11 of the adjustable collet is formed integral with a base 12 which is provided with a flange 13 for engagement with one of the side faces of the balance cap 1. A retainer lat is secured to the adjustable collet, by means such as a screw 15, to engage the other face of the balance cap and retain the adjustable collet in the slot 10. The screw 15 also functions to clamp the adjustable collet in place by frictional engagement of the flange l3 and the retainer 1 1 on opposite sides of the balance cap 1.

The base 12 of the adjustable collet is provided with an opening through which the terminal of the end portion 7 of the hair spring projects and is suitably keyed.

It will be seen from the foregoing, that before the adjustable collet can be moved in either direction in the slot 10, it will be necessary to loosen the hair spring in the fixed collet by turning the screw 9. Thereafter, the adjustable collet can be shifted in the slot 10 to lengthen or shorten the hair spring as desired.

It will be understood that the retainer 14, may in some cases be countersunk in the face of the balance cap 1 for passage of the regulator across or abreast of the adjustable collet in types of movement where this may be necessary.

WVhile I have herein shown and described one specific form of my invention, I do not wish to be limited thereto except for such limitations as the claims may import.

I claim 1. In a watch balance, a balance cap provided with a slot therein, a collet adjustably mounted in said slot, a hair spring having its terminal end keyed to said adjustable collet, and stationary means carried by said balance cap at a point remote from said collet, in the direction of wind of the hair spring for adjustably anchoring said hair spring.

2. In a watch balance, a balance cap provided with a slot therein, a collet adjustably mounted in said slot, a hair spring having its terminal end keyed to said adjustable collet, and a stationary collet carried by said balance cap adjacent one end of said slot and connecting with the hair spring at a point remote from the adjustable collet with respect to the direction of Wind of said hair spring.

3. In a watch balance, a balance cap provided with a slot therein, a collet adjustably mounted in said slot, said adjustable collet comprising a base member and a retainer plate, a hair spring having its terminal end keyed to said adjustable collet and a stationary collet carried by said balance cap ad acent one end of said slot and connectmg With the hair spring at a point remote to the adjustable collet with respect to the direction of wind of said hair spring.

4. In a watch balance, a balance cap provided with an arcuate slot, a collet slidably fitted in said slot and capable of reciprocable adjustment therein, means for holding said collet in frictional engagement with said balance cap, a hair spring having its terminal end keyed to said adjustable collet and a stationary collet carried by said balance cap, adjacent one end of said slot and connecting with said hair spring at a point remote from the adjustable co'llet for adj ustably anchoring said hair spring.

5. In a watch balance, a balance cap provided with a slot therein, a two-part collet slidably fitted in said slot and capable of reciprocable adjustment therein, said adjustable collet comprising a base member having a slot-engaging portion and a retainer plate in engagement with the said slot engaging portion, said plate disposed upon the upper face of said balance cap and arranged over said slot, means for connecting said plate and base member and securing the same against the vcap to lock the collet in position, a hair spring having its terminal end fixed to said adjustable collet, and means carried by said cap adjacent one end of said slot, and in connection with said hair spring at a point remote from the adjustable collet for adjustably anchoring the hair spring.

In testimony whereof I afiix my signature in presence of two Witnesses.

DERWOOD B. RAFF. l/Vitnesses:

Rosa. 0. STUBBINS, THOMAS U. Comm.

Copies 01 this patent may be obtained for five cents each, by addressing the Commissioner or Iatentl,

Washington, D. 0." 

